In traditional cheese production, pretreated milk without previous concentration is added to and mixed with additives necessary for the production of cheese, such as rennet and/or other proteolytic enzymes for coagulation of the milk. By concentrating the milk prior to production subsequent stages of production can be carried out with a reduced process flow and with processing equipment requiring less space and expense as a result of this. In addition the concentration permits reduction of the quantity of additives needed for coagulation of the milk, permitting more effective utilization of these additives.
U.S. application Ser. No. 07/782,321, filed Oct. 24, 1991, corresponding to Swedish Patent Application No. 9003540-3, described how the cheese production method described above, in which milk is concentrated, can be made more effective and can be modified such that it can be carried out completely automatically and on a rational industrial scale. According to this U.S. patent application no., which is incorporated herewith in its entirety as a reference, these further advantages are achieved through concentrating the pretreated milk to a dry matter (DM) content corresponding to the DM content in the finished cheese and through drawing off and packaging the mixture of concentrated milk and additives directly into distribution-ready packagings, i.e. performing the separation of the whey during the concentration of the milk so long as no further subsequent separation of whey is required, allows the coagulation and forming of the milk to occur without need for separate coagulation or forming.
In the above-noted U.S. patent application it is further proposed that the concentration of the pretreated milk should preferably be carried out through use of an ultra-filtering device with a filter having a pore size such that all proteins, fats and other constituents valuable for cheese production occurring in the milk are retained in it as pre-cheese retained matter through filtering the extracted concentrated milk and permitting the whey to pass freely through the filter.
According to the above-noted application, in conventional production of cheese the milk pretreated for cheese production is mixed with additives necessary for coagulation of the milk, most frequently rennet and/or other proteolytic enzymes, to form a gel. When the gel has reached a predetermined solidity, the gel is broken up with the aid of special tools, known as breaking tools, so that smaller cubes with the desired size are formed. The broken up cheese mass is then subjected to mechanical treatment at the same time as the mass is heated according to a preset scheme, through which the whey is pressed out of and separated from the mass. After conclusion of the treatment/heating the mass is placed in molds which determine the cheese's final shape, after which the cheese thus formed are packaged in packagings of different types intended for distribution.
The conventional procedure described is time-consuming and most frequently requires manual monitoring and control in order to maintain the constant process conditions necessary for the desired quality of cheese during each one of the production stages. The procedure is, in addition, one which, form the point of view of equipment, requires a great deal of space and can only with difficulty be automated and carried out on a desired rational industrial scale.
Problems of the above type are solved at least partly through another known production procedure which takes as its starting point the fact that the pretreated milk is first concentrated through a liquid fraction (whey) being separated from the milk and the concentrated (protein- and fat-enriched) milk obtained is then added to and mixed with additives necessary for coagulation of the milk. Here it has proven to be particularly valuable to concentrate the milk through ultra-filtering, through which the separated liquid fraction can be made practically free from protein, fat and other constituents desirable for cheese production occurring in the milk which are thus retained in the concentrated milk extracted as pre-cheese retained matter. According to this known technology, among other things, the advantage is gained that practically all valuable constituents occurring in the milk can be retained and, depending on the degree to which the milk is concentrated, the amount of rennet and/or proteolytic enzymes added for the coagulation can be reduced to a corresponding degree with cost savings gained thereby. Further, the advantage is gained that the production process after the milk concentration can be carried out with considerably less process equipment requiring space and investment than the previously described conventional cheese production.
It has, however, been shown that the last described known production procedure can further be made more effective to yield a procedure for cheese production which functions well on a rational, industrial scale and which can in addition be carried out in a practically entirely automated manner.
This aim is achieved according to such a procedure, described in the above-noted application, through the fact that the procedure described in the introduction is given the characteristics that the milk is concentrated to a DM content corresponding to the DM content in the finished cheese and that the mixture of concentrated milk and additives is drawn off and packaged directly into distribution-ready packagings.
Through concentrating the milk from the beginning to a DM content corresponding to the DM content of the finished cheese a subsequent further whey separation stage is thus avoided, at the same time as such a concentration entails that the mixture of concentration milk and additives can be packaged directly into the finished packagings with a previous coagulation stage. In the method according to the above-noted application the coagulation of the milk thus occurs practically entirely in these packagings.
According to the above-noted application it has proved to be possible and particularly valuable to use as packagings for the coagulated cheese mass the same type of packagings as is often used to package liquid foods such as milk, juice, etc., which are produced with the aid of modern, rational packaging machines of the type which both forms, fills and closes the finished packagings. A well known example of such a packaging is the packaging manufactured from a strip of plastic coated paper of the type TETRA BRIK (trade mark).
For example it has been shown, according to the above-noted application, to be possible to produce a cheese with a chemical composition with regard to fat, total protein, salt and DM content corresponding to a semi-solid, ripe cheese of SCT. Paulin type (popularly called a soft Danbo) with the use of the following additives:
glucone lactone (GDL, chemical acidification agent) which on slurrying in the water converts from a pH-neutral product to an acid product containing lactic acid with a pH value of 5.2.
Colorants PA1 Flavourings PA1 NaCl PA1 Rennet
Through suitable choice of additives in this sphere which are in themselves known it is thus possible continuously to produce and prepare for distribution cheeses of different types on a rational industrial scale in the manner according to the above-noted application which, in contrast to the hitherto known procedures, can be carried out with a minimum number of involved production stages and which, through the included full concentration of the milk before the addition of the additives selected for the cheese production, offers the substantial advantage that the mixture of the milk and the aforesaid additives can be filled directly and packaged into distribution-ready packagings in such a way that the coagulation of the milk and also the forming of the cheese occur essentially entirely in these packagings.
The cheese produced by the method according to the above-noted U.S. patent application complies in practice with all requirements set for cheese as far as concerns taste, colour, consistency, maturity, DM content and content of fats, protein, salt and other desirable constituents. However, the cheese produced by this process either lacks completely or only exhibits imperfectly developed holes or tubular passages which contribute to giving certain types of cheese their typical and easily recognizable appearance which is generally regarded by the consumer as a guarantee of a "genuine" cheese quality.